DE3316366A1 - OVEN CASE FOR A DC ARC FURNACE - Google Patents

Abstract

1. A furnace vessel for a d.c. arc furnace, comprising a contact device which is arranged in the central area of the vessel base and which serves to discharge the anode current, where this contact device comprises a plurality of metallic base electrode pins which extend in parallel to the vessel axis and are retained in refractory material, and of a cooled current outlet which is arranged below the furnace vessel, characterized in that each base electrode pin (4) is detachably fixed to the vessel (5) by means of a retaining device (6, 7, 16), is individually insulated from the vessel (5), extends through perforated refractory bricks (2) so as to be insertable and extractable, and is individually connected to the cooled current outlet (14).

Description

22831 - C / Un. - 4 - May 4, 1983

The invention relates to a furnace vessel for a direct current arc furnace, with a contact device provided in the middle of the vessel bottom to divert the anode current, this contact device consisting of a plurality of parallel to the vessel axis, held in the refractory material, metallic bottom electrode pins as well as a cooled current conductor arranged below the furnace vessel.

In addition to ground contact with a variety of metal pins, which are each firmly connected to the upper end of a metal plate (DE-OS 29 50 890) are also contact electrode arrangements known (DE-OS 29 05 553), in which the contact pins are firmly connected to a base plate arranged below the furnace vessel bottom are. This base plate is over vertically extending walls connected to the underside of the vessel bottom, and the space is traversed by a cooling stream.

With the known bottom electrode arrangements, it is not possible to the pins, which are subject to different levels of wear, without changing individually without dismantling work. Also is it is necessary when changing the bottom electrode bundle that Refractory lining to be added to the entire floor area.

The object of the present invention is to provide a furnace vessel of the initially mentioned named type whose structure enables the

Changing the bottom electrode pins individually without significant assembly work, without the need to renew the feeding in the bottom area. This object is achieved by the characterizing features of claim 1.
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Advantageous further developments of the invention are set out in the subclaims executed.

22831 - C / Un. - 5 - May 4, 1983

The invention makes it possible to use individual bottom electrode pins to be changed depending on the wear and tear. Because the bottom electrode pins are inserted into perforated bricks that are built into the brickwork of the stove are integrated, it is not necessary to change the to renew the entire brick lining in the floor area.

Compared to the furnace vessels according to the aforementioned DE-OS 29 50 890, an advantageous change from below is possible.

The wear of the individual pins is through separate temperature control or pressure control possible. This is because temperature sensors or pressure gauges (in the case of a Gas cooling). The pressure gauges indicate a drop in pressure when the bottom electrode pins are melted. When using bundled contact pins, one Local control of the wear of the pins is not possible.

Secondly, the sensors attached to the outer end can also be used to monitor the wear and tear of the ground lining will.

The temperature sensors attached to the individual bottom electrode pins can also signal local overheating at the bottom of the vessel.
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The fact that the individual bottom electrode pins compared to the If the bottom of the vessel is insulated, no additional insulation is necessary.

The invention is explained in more detail with reference to the accompanying drawing.

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22831 - C / Un. - 6 - May 4, 1983

The bottom of the vessel is denoted by 5, and 1 shows the hearth lining.

The bottom electrode pins 4 are in the vessel bottom 5 from below arranged so that they can be brought in and out. They are individually isolated from the floor jacket, partly by the refractory perforated bricks 2, which they penetrate, partly through ceramic disks 8 and 9. The space between the bottom electrode pin 4 and the perforated stones 2 is filled with a sealing compound 3.

The pins 4 are each connected to the anode current conductor via a contact clamp 10 made of steel with explosive-plated Cu connection lugs 14 connected. This derivation consists of Cu tubes that are arranged in a circle under the bottom of the vessel.

On the outside of the vessel bottom 5 there is a holding device in each case attached to the detection of the bottom electrode pin 4 serves. This holding device consists of a fastening claw (6) welded to the base (5) and into which a holding sleeve 7 is inserted. In the space between the claw 6 and the holding sleeve 7, a pin 4 is arranged on the bottom electrode Confederation 16 recorded. The federal government is opposite the holding parts 6 and 7 isolated by the ceramic insulating rings 8 and 9.

In the example shown flows through the pipes that the Form anode current discharge line 14, inert gas which is supplied or discharged through the connection 11. The individual pins 4 are connected to the cooling circuit.

The anode current discharge 14 is arranged in a ring around the vessel axis.

22831 - C / Un. - 7 - May 4, 1983

The individual pins 4 form groups which, in particular, are arranged around the extended axes of the cathode electrodes are.

In the example shown is at the bottom of the pin 4 a temperature sensor 12 is connected.

The connection of the bottom electrode pins 4 to the anode current lead 14 takes place in each case via a contact terminal 10 with a metal Stretch band 13.

The tube of the anode current discharge line 14 is above the vessel bottom 5 an insulating terminal 15 connected.

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Claims (9)

Mannesmann Aktiengesellschaft May 4, 1983 Mannesmannufer 2 22831 - C / Un. Düsseldorf furnace vessel for a direct current arc furnace claims 1. Furnace vessel for a direct current arc furnace, with a contact device provided in the middle area of the vessel bottom to divert the anode current, this contact device consisting of a large number of metal bottom electrode pins, held in the refractory material and running parallel to the vessel axis, as well as a cooled current conductor arranged below the furnace vessel,
characterized, that from below in and out of the vessel bottom (5), individually insulated from the vessel bottom (5), common refractory Perforated stones (2) penetrating bottom electrode pins (4) the cooled anode current discharge (14) are connected. ο ο ι υ ο υ υ 22831 - C / Un. - 2 - May 4, 1983 2. Furnace vessel according to claim 1, characterized in that that on the outside of the vessel bottom (5) each has a holding device (6, 7, 8, 9) for the pin (4) is attached. 5 3. Furnace vessel according to claim 2, characterized in that the holding device consists of one welded to the bottom (5) There is a fastening claw (6) into which a retaining sleeve (7) is inserted is, in which between the claw (6) and the retaining sleeve (7) existing space on the bottom electrode pin (4) arranged, opposite the holding parts (6, 7) insulated collar (16) is recorded. 4. furnace vessel according to claims 1 to 3, characterized in that individual bottom electrode pins (4) to the cooling circuit of the Anode current lead (14) are connected. 5. Furnace vessel according to Claims 1 to 4, characterized in that the anode current discharge line (14) is annular around the vessel axis is arranged. 6. furnace vessel according to claims 1 to 5, characterized in that the cooling circuit of the anode current discharge line (14) by a Inert gas circuit (11) is formed. 7. furnace vessel according to claims 1 to 6, characterized in that on the bottom electrode pin (4) a temperature (12) and / or Pressure gauge is connected. 22831 - C / Un. - 3 - May 4, 1983 8. furnace vessel according to claims 1 to 7,
characterized, that the bottom electrode pins (4) each clamp over a contact (10) with a metal expansion band (13) on the anode current lead (14) is connected. 9. furnace vessel according to claim 8,
characterized, that the anode current discharge (14) via an insulating terminal on the Vessel bottom (5) is connected.